Forum Schedule Fall 2025

Planetesimal (debris) disks offer valuable insights into the formation, evolution, and architecture of exoplanetary systems. In particular, their substructures -- now commonly observed across various wavelengths -- provide indirect evidence of dynamical perturbations, such as those from yet-unseen exoplanets. However, most existing studies of planet-debris disk interactions adopt simplified models that treat the disks as swarms of massless planetesimals. This is at odds with observations suggesting that debris disks may contain a few to tens of Earth masses of material. What role do massive debris disks play in their dynamical evolution, and how do they influence interpretations of observed substructures? In this talk, we address these questions using orbit-averaged secular dynamics. We demonstrate that the disk's gravity can significantly shape both its radial and vertical structure, giving rise to features such as gapped (double-ringed) morphologies, warps, and spiral patterns. Notably, these effects can arise even when the disk is less massive than the perturbing planet, challenging common assumptions. These findings are particularly timely, as JWST observations aim to detect or rule out planetary companions in systems hosting debris disks. Our findings suggest that planetary inferences based on massless disk models may be compromised, underscoring the need for more realistic dynamical treatments.